| dc.description.abstract | Perovskite materials due to their excellent photoelectric properties, including high PLQY, narrow FWHM and adjustable luminescence wavelength, can be applied to solar cells, lasers, photovoltaic devices, and LEDs, etc., have become a major research hotspot in academia and industry in recent years. Nevertheless, the red-emitting all-inorganic perovskite CsPb(BrxI1-x)3 is sensitive to moisture and air, which greatly limits its commercial application. Therefore, improving the stability of the material is one of the focuses of current research.
In this study, bromine iodine mixed perovskite CsPb(BrxI1-x)3 quantum dots (QDs) with different luminescent wavelengths were synthesized by hot injection method without polar solvent, with different ligands OLA and APTES ((3-Aminopropyl) triethoxysilane) and adjusting the ratio of halogen. In addition, in order to increase the application value of QDs, the ratio of halogen which is closest to the academic research of red luminescence at 633 nm was selected and added into PMMA matrix to prepare films. The luminescent properties and stability of the films were analyzed and compared. The results show that APTES is helpful to enhance the stability of films. However, the stability of the film exposed to air and moisture still needs to be improved.
Therefore, in this study, TEOS (Tetraethyl orthosilicate) sol-gel reaction was introduced into APTES based QDs to coat the QDs with denser SiO2 to isolate air and moisture, thus effectively improving the stability of the films. Finally, in order to enhance the uniformity of light emission, we doped SiO2 nanospheres to increase the Mie scattering. The results show that the PLQY of the films increases with the increase of the doping amount. The red light films with PLQY up to 45% and lasting for one month, which are expected to be used in WLED and display backlights in the future. | en_US |